It is a challenge to maintain the links from an article in one language to all of the versions of that article in other languages. Each time a new version is introduced, changes name, or is deleted, all of the other versions should be updated.

There is an interwiki bot coded in Python by Rob W.W. Hooft (c) 2003. It requests an article, parses interwikis and checks if the other wikis are up to date.

From the .py file:

Script to check language links for general pages. This works by downloading the page, and using existing translations plus hints from the command line to download the equivalent pages from other languages. All of such pages are downloaded as well and checked for interwiki links recursively until there are no more links that are encountered. A rationalization process then selects the right interwiki links, and if this is unambiguous, the interwiki links in the original page will be automatically updated and the modified page uploaded.

The robot tries to be soft on the wikipedia server: it uses the new Special:Export feature to get more than one page in one request, and it waits between requests. The robot will (unless changed) not modify more than one page per minute.

This robot has a growing operator community.

Before being used on a wiki, its community should authorise such a bot to update the wiki. it can be tested on a small number of pages to demonstrate its purpose.

The best thing is to have an operator for each language that wants to run the robot.

Operators of the bot, and in fact all people that want to discuss the implementation or the usage of this code, are welcome to join the mailing list pywikipediabot-users@lists.sourceforge.net by subscribing at the mailinglist information page